HHS Special Exposure Cohort Designation:

General Atomics, La Jolla, California

HHS Designation of Additional Members of the 

Special Exposure Cohort 

under the 

Energy Employees Occupational Illness Compensation Program Act of 2000 

Designating a Class of Employees 

General Atomics 

La Jolla, California
HHS Special Exposure Cohort Designation:

General Atomics, La Jolla, California

Page 2

I. Designation 

I, Sylvia M. Burwell, Secretary of the U.S. Department of Health and Human Services, designate the 

class of employees defined in Section II of this report for addition to the Special Exposure Cohort 

(SEC), as authorized under the Energy Employees Occupational Illness Compensation Program Act 

of 2000 (EEOICPA), 42 U.S.C. § 7384q.

September 25, 2014 [Signature on File]

Date Sylvia M. Burwell

II. Employee Class Definition

All Atomic Weapons Employees who worked for General Atomics at its facility in La Jolla, 

California, during the period from January 1, 1960, through December 31, 1969, for a number 

of work days aggregating at least 250 work days, occurring either solely under this 

employment, or in combination with work days within the parameters established for one or 

more other classes of employees included in the Special Exposure Cohort.

III. Designation Criteria and Recommendations

Pursuant to 42 U.S.C. § 7384q, for the class defined in Section II of this report, the Secretary has 

determined, and the Advisory Board on Radiation and Worker Health (Board) has recommended, that

(1) it is not feasible to estimate with sufficient accuracy the radiation dose that the class received; 

and

(2) there is a reasonable likelihood that such radiation dose may have endangered the health of 

members of the class.

The SEC final rule states in 42 C.F.R. § 83.13(c)(1) that it is feasible in two situations to estimate the 

radiation dose that the class received with sufficient accuracy. First, the rule states that radiation 

doses may be estimated with sufficient accuracy if the National Institute for Occupational Safety and 

Health (NIOSH) has established that it has access to sufficient information to estimate the maximum 

radiation dose, for every type of cancer for which radiation doses are reconstructed, that could have 

been incurred under plausible circumstances by any member of the class. Alternatively, radiation 

doses may be estimated with sufficient accuracy if NIOSH has established that it has access to 

sufficient information to estimate the radiation doses of members of the class more precisely than a 

maximum dose estimate.

NIOSH determined that there is insufficient information to estimate the radiation dose of individual 

members of the class with sufficient accuracy under the two abovementioned situations. The Board, 

pursuant to 42 U.S.C. § 7384q, advised the Secretary to designate the class as an addition to the SEC 

in a letter received by the Secretary on September 3, 2014.
HHS Special Exposure Cohort Designation:

General Atomics, La Jolla, California

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IV. Designation Findings

Infeasibility of Estimating Radiation Doses with Sufficient Accuracy

The Secretary designates the class of employees covered by this report based upon the findings 

summarized below.

• Principal sources of internal radiation for members of the proposed class included exposures to 

uranium isotopes (depleted, natural, enriched, and recycled), plutonium, thorium, tritium, and 

other fission and activation products associated with radiological research and production 

activities, including reactor and accelerator operations.

• NIOSH has determined that it is necessary to remove the area-specific and monitoring criteria 

from the class description associated with NIOSH’s 2006 evaluation of SEC-00064 exposures for 

the period from January 1, 1960, through December 31, 1969, because of the potential for 

difficulties in implementing the class definition. Additionally, due to the issues identified during 

ongoing dose reconstruction and methodology reviews conducted by NIOSH and the Board after 

implementation of SEC-00064, NIOSH has determined that infeasibilities associated with 

sufficiently accurate reconstruction of internal exposures during that period extend beyond the 

assessment of thorium exposures as was presented in NIOSH’s 2006 evaluation of General 

Atomics. 

• NIOSH lacks sufficient information that would allow it to estimate with sufficient accuracy the 

potential unmonitored internal exposures, including unmonitored uranium, thorium, tritium, and 

fission and activation products, to which the proposed class may have been subjected during the 

period from January 1, 1960, through December 31, 1969.

• Principal sources of external radiation for members of the proposed class included exposures to 

radiation fields associated with reactor, accelerator, and fuel production operations and 

experiments. NIOSH will determine through discussion with the Board to what extent external 

radiation doses from operations can be reconstructed.

• NIOSH considers that sufficiently accurate reconstruction of medical dose for General Atomics 

workers is feasible by using claimant-favorable assumptions, as well as applicable protocols 

specified in the complex-wide ORAUT-OTIB-0006, Technical Information Bulletin: Dose 

Reconstruction from Occupationally Related Diagnostic X-Ray Procedures.

• NIOSH lacks sufficient information, which includes biological monitoring data, sufficient air 

monitoring information, or sufficient process and radiological source information, that would 

allow it to estimate with sufficient accuracy the potential unmonitored internal exposures, 

including unmonitored uranium, thorium, plutonium, tritium, and fission and activation products, 

to which the proposed class may have been subjected during the period from January 1, 1960, 

through December 31, 1969.

• Although NIOSH found that it is not possible to completely reconstruct radiation doses for the 

proposed class, NIOSH intends to use any internal monitoring data that may become available for 

an individual claim (and that can be interpreted using existing NIOSH dose reconstruction 

processes or procedures). Depending on the outcome of its discussion with the Board, NIOSH 

intends to either completely reconstruct external exposures, or to use any external monitoring data 
HHS Special Exposure Cohort Designation:

General Atomics, La Jolla, California

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that may become available for an individual claim (and that can be interpreted using existing 

NIOSH dose reconstruction processes or procedures).

• Pursuant to 42 C.F.R. § 83.13(c)(1), NIOSH determined that there is insufficient information to 

either: (1) estimate the maximum radiation dose, for every type of cancer for which radiation 

doses are reconstructed, that could have been incurred under plausible circumstances by any 

member of the class; or (2) estimate the radiation doses of members of the class more precisely 

than a maximum dose estimate.

• The Board concurred with NIOSH’s recommendation to add the proposed class of workers to the 

SEC.

Health Endangerment

The Secretary established the health endangerment determination for the class of employees covered 

by this report based upon the findings summarized below.

(1) Pursuant to 42 C.F.R. § 83.13(c)(3), NIOSH established that there is a reasonable likelihood 

that such radiation doses may have endangered the health of members of the class. Pursuant 

to 42 C.F.R. § 83.13(c)(3)(ii), NIOSH specified a minimum duration of employment to satisfy 

this health endangerment criterion as “having been employed for a number of work days 

aggregating at least 250 work days within the parameters established for this class or in 

combination with work days within the parameters (excluding aggregate work day 

requirements) established for one or more other classes of employees in the Cohort.”

(2) NIOSH did not identify any evidence from the petitioners or from other resources that would 

establish that the class was exposed to radiation during a discrete incident likely to have 

involved exceptionally high-level exposures, such as a nuclear criticality incident, as defined 

under 42 C.F.R. § 83.13(c)(3)(i). 

(3) The Board concurred with NIOSH’s finding that the health of the class may have been 

endangered and defined the class according to the 250-work day requirement specified under 

42 C.F.R. § 83.13(c)(3)(ii).

V. Effect and Effective Date of Designation

The Secretary submits this report on the designation of one additional class to the SEC for review by 

Congress, pursuant to 42 U.S.C. §§ 7384l(14)(C)(ii) and 7384q(c)(2)(A), as amended by the Ronald 

W. Reagan National Defense Authorization Act for Fiscal Year 2005, Pub. L. No. 108-375 (codified 

as amended in scattered sections of 42 U.S.C.). Pursuant to 42 U.S.C. § 7384l (14)(C)(ii), as 

amended by the Ronald W. Reagan National Defense Authorization Act for Fiscal Year 2005, Pub. L. 

No. 108-375 (codified as amended in scattered sections of 42 U.S.C.), the designation in this report 

will become effective 30 days after the date of this report’s submission to Congress “unless Congress 

otherwise provides.”
HHS Special Exposure Cohort Designation:

General Atomics, La Jolla, California

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VI. Administrative Review of Designation

The health endangerment determination of the designation provided in this report may be subject to 

an administrative review within HHS, pursuant to 42 C.F.R. § 83.18(a). On the basis of such a 

review, if the Secretary decides to expand the class of employees covered by this designation, the 

Secretary would transmit a supplementary report to Congress providing the expanded employee class 

definition and the criteria and findings on which the decision was based.